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Women in their 30s and 40s anxious about their dwindling prospects of getting pregnant have become a booming market for a new arm of medicine: fertility testing.
Thousands of women have flocked to have their “ovarian reserve” measured, and have made major life decisions — like whether to try to have kids sooner — based on the results of these tests, which typically cost between $150 and $350. Ovarian reserve, or the amount of eggs a woman has left in her ovaries compared to other women her age, was thought to be a key metric of reproductive capacity.
But a new study out in JAMA shows that these tests are often useless for many of the women to whom they’re marketed.
While ovarian reserve tests can still inform would-be moms about their chances of success at harvesting eggs for egg freezing or for in vitro fertilization, they are not necessarily a good predictor of a woman’s ability to conceive through sex. Getting pregnant ultimately depends on many, many complicated factors in both women and their partners — not simply how many eggs remain in a woman’s ovaries.
How fertility testing became a booming business
For the first time, more American women are having babies in their 30s than in their 20s — part of the gradual increase over the past four decades in the average age Americans becoming parents.
But getting pregnant in your 30s or 40s can also come with a lot of uncertainty about whether it’s even possible conceive, and how much time might be left before infertility sets in.
Enter fertility testing, a relatively new industry that claims to be able to help women answer these burning questions.
Several online companies and fertility centers now offer tests of ovarian reserve. At Future Family, the $149 Fertility Age Test promises to deliver “insight into your current and future fertility” in the privacy of your own home. For $150, the at-home Let’s Get Checked test determines if a woman’s “pregnancy chances are lower than what is expected at her age.” At Shady Grove Fertility, the largest fertility center in the country, ovarian reserve testing is “part of the initial fertility evaluation.” There, the test costs $325 without full or partial insurance coverage — and promises “no more guessing” about fecundity.
Researchers are debunking ovarian reserve testing for women with no history of infertility
But researchers are increasingly finding these tests are meaningless for predicting whether a woman will get pregnant — at least in women who have no history of infertility (the type of women these tests are marketed to).
For the new study in JAMA researchers tracked 750 women aged 30 to 44 years with no history of infertility. The women had their ovarian reserve tested using three common hormonal biomarkers of ovarian reserve — AMH, FSH, and inhibin B — in the blood and urine, and they were followed for up to a year.
The researchers thought women with “diminished ovarian reserve” would have a harder time getting pregnant. (Women are born with a set number of eggs that are released with each menstrual cycle and slowly die over time, a process that ends in menopause.)
But the researchers found there was actually no correlation between a woman’s egg stores and her ability to conceive. Women with a low AMH value or a high FSH reading — markers of diminished ovarian reserve — weren’t any less likely to eventually test positive on a pregnancy test than women with a normal AMH level. (Inhibin B measures were also not associated with fertility outcomes.)
“These tests are a great measures of ovarian reserve, how many eggs you have,” said study lead author Anne Zweifel Steiner, a professor of obstetrics and gynecology at the University of North Carolina, Chapel Hill, “but they don’t work to predict a woman’s reproductive potential.”
Until her study came along, Steiner said many in the medical community thought it was plausible these tests could determine fertility. After all, in people who were undergoing IVF, hormone values like AMH and FSH often correlated with how well a woman would respond to IVF medications and how easily she would get pregnant. “So we thought it would also be a good predictor of a woman’s natural fertility,” Steiner added.
But evidence is now mounting that’s not the case. In another trial, published in 2015, researchers looked at AMH levels as a marker for predicting fertility, and they also didn’t find any association.
A dreaded “diminished ovarian reserve” finding might push a woman to consider freezing her eggs, or to rush to get pregnant. A normal test result, on the other hand, might lead a would-be-mom to delay getting pregnant. Now, acting on these results appears to be misguided.
One good predictor of a woman’s ability to conceive: her age
Companies and fertility centers need to rethink how they sell these tests to women, Steiner said. “We had reason to believe [biomarkers measuring ovarian reserve] were going to be predictive of fertility. We didn’t have any proof otherwise. But as we’re gathering more evidence, we’ll need step away from saying it’s a great fertility test.”
Samantha Pfeifer, a professor of obstetrics and gynecology and clinical reproductive medicine at Weill Cornell, wasn’t entirely surprised by the findings.
“When you look at fertility, you’re looking at numbers of eggs, egg quality, receptivity of the uterus — so many other things that are important for fertility, not just ovarian reserve,” Pfeifer said. “This new study is terrific. It reiterates the fact that women with a low ovarian reserve may be able to achieve a pregnancy. This is really good news.”
So if ovarian reserve isn’t a great predictor of fertility in women, then what is?
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Age, Steiner said. “Everybody wants something better,” she added. “I would love to find something in addition to age. But it’s the best we have.”
The good news is that a woman doesn’t suddenly become drastically less fertile at 35, even though the rhetoric around “geriatric pregnancies” by that age might suggest otherwise.
“It’s much more of a gradual decline,” Steiner said. “Yes, your ability to become pregnant is slightly lower once you hit 36 or 37, and slightly lower at 38 or 39. But it’s not like someone drops off the cliff at age 35.”
